Machine for drawing threads in fabrics



Oct. 13, 1931. r H, CORRALL ET AL 1,827,706

MACHINE FOR DRAWING THREAPS IN FABRICS Filed Aug. 30. 1930 2 Sheets-Sheet l Fl G 5 jmiewiou Oct. 13, 1931. H. COVRRALL ET AL 1,827,706

MACHINE FOR DRAWING THREADS IN FABRICS Filed Aug. 30. 1950 2 sheets-sheez 2 Herbaldarl-all James 174 12759 r mmed a. 13, 1931 UNITED. STATES PATENT OFFICE.

HERBERT CORRALL, OF HELENSBURGH,

AND JAMES HEGGIE, 0F CLYDEBANK,

SCOTLAND, ASSIGNORS TO THE SINGER MANUFACTURING COMPANY, OF ELIZABETH, NEW JERSEY, A CORPORATION OF NEW JERSEY' MACHINE FOR DRAWING THREADS IN FABRICS Application filed August 30, 1930, Serial No. 478,808 and in Great Britain September 4, 1929.

This invention, which is a development of that forming the subject of U. S. Patent 1,704,881 dated 12th March, 1929, relates to machines for drawing threads in fabrics of the type having a presser bar and a piercer bar above the throat plate and a feeding device and a rotary thread cutter below the throat plate.

In accordance with the invention the press er foot is formed as an open or skeleton frame secured to the rearward side .of which is one limb of a U-shaped or reflex spring of wire the return bend of which rests on the forward side of said frame and of which the other limb is free and constitutes a resilient fabricdepressing member projecting below the lower face of the presser foot and adapted to enter a slot extending in the direction of feed and bounded on one side by the marginal edge of a cut-away in the throat-plate.

The other side of each such slot is formed by one longitudinal edge of a blade sprin anchoredto the throat plate at its rearwar end and at its forward end overhung by a ledge on the throat plate against the underside of which the blade spring bears resilient- 1y.

The blade spring has an orifice for penetrationby the piercer, such orifice being countersunk to present a ledger blade co-operative with the rotary cutter.

In the drawings Figs. 1 and 2 are, respectively, a plan view and a vertical longitudinal section on the line 2-2 of Fig. 1, showing the presser foot; Fig. 3 is a plan View of the throat plate. Fig. 1 is an end elevation showing the assembly of the presser foot, piercer blade and rotary cutter, showing also the throat plate in section on the line 44 of Fig. 3; Fig. 5 is a view similar to Fig. 4 except that the throat plate is shown in section on the line 5'5 of Fig. 3; Fig. 6 is a view at right angles to Fig. 5; the throat plate being shown in section on the line 66 of Fig. 5; Fig.7 is an end elevation showing inter alia the feed dog, the feed rock shaft, and the feedlift rock shaft; Fig. 8 is a detail view of the presser foot assembly showing the balance member therefor; Fig. 9 is apart side elevation part section throughthe machine frame showing the operative connections between the upper driving shaft and the lower shafts.

1 denotes the presser foot which is formed as an-open or skeleton frame on the longitudinal sides of which are provided upstanding lugs 3, 4 which are penetrated by pivot pins 5, 6 screw-threaded, respectivelyyinto the lower ends of shanks 7, 8 depending from the presser-bar 9. The upper ends of the shanks 7, 8 are interconnected in manner already known by a balance member 10 (Fig. 8) journalled within a block 10 secured to the lower end of the presserbar 9 so that the shanks 7, 8 are free to perform limited reciprocal vertical movements.

Secured by means of a screw 11 to the rearward side of the presser-foot 1 adjacent to each longitudinal side thereof is one limb 12 of a reflex wire spring 12, 13 of which the return bend 14 rests on the forward side of said frame and of which the limb 13 is free and constitutes a resilient fabric-depressing member projecting below the lower face of the presser foot and adapted to enter a slot 15 extending in the direction of feed. The outer boundary of each slot 15 is defined by one longitudinal edge 17 of a cut-away 17, 18 in the throat plate 16, said edge 17 being parallel with the line of feed. The inner boundary of each slot 15 is defined by one longitudinal edge of ablade spring 19 anchored by means of a screw 20 to the rearward end of the throat plate and traversing the cut-away 17, 18, the forward end of the blade spring 19 being overhung by one lateral edge 18 of the cutaway, against the underside of which edge said forward end of'ihe blade spring bears resiliently.

Formed in the blade spring 19 is an orifice 21, for penetration by the piercer blade indicated at 22, the orifice 21 being countersunk to form a ledger blade for cooperation with the rotary cutter indicated at 23 and carried by a shaft 23, the cutter in its rotation sweeping the underside of the blade spring 19 at the orifice 21, the blade spring flexing slightly but being prevented from vibrating or rattling.

The piercer blade 22 has double serrated edges 24 (Fig. 6) disposed transversely of the line of feed.

25 denotes the vertically reciprocating piercer-carrying bar. 7

Two sets of feed dog serrations 26' project upwardly from the feed dog 26' through slots 27 formed longitudinally in the throat plate 16, one alongside each edge 17 of the cat-awa u, 18. V 7

1 lnthe'assemblyshown in Fig; 9,28 de- 7 notes the upper rotary driving shaft which is operatively connected to the rotary cutter shaft 23, the feed-lift rock shaft29 and the feed-lift rock shaftc30 (Fig. 7 journalled I 1 in the bed of the machine frame. The shaft 28 isjournalled in the arm 31 of the machine frame and carries withinthe head 32 of the arm a crank 83 operatively connected through a link 34 to the piercer-carrying bar 25. I 20. "Weclaim:-, v if '1. In a thread drawing machine, incom-' bination; a throat plate presenting slots, a rotary cutter below said throat plate, a,re-'

ciprocatory fabric piercer adaptedto pene- -trate said throat-plate, a'presser-bar above saidfthroat plate, a presser-foot carried by said resser-bar, said presser-foot formed as an'open frame having sides extending in the direction of feed, and reflex springs-each hav 7 '.,lI1g one limb secured to said frame adjacent to oneof-said longitudinalsides, the other limb of each spring'being free and projecting beneath thelowerface of said presser foot and adapted to enter'one'of said slots.

35 2. In a thread drawing machine, in com.-

' bination, a throat plate having a cutawayya reciprocatory piercer bar above said throatv plate, a fabric piercer carried by'said piercer bar, a rotary thread cutter below said throat 40 plate, a blade spring anchored at one end only to said throat plate,'extending across said cut-away and at its other end bearing resiliently against the under side of; said throat-plate, said blade spring having an ori-i fice penetrable by said piercer, the edge of said orifice constituting a ledger blade 00-' operating with said rotary cutter. I

' In testimony whereof we have signed our names to this specification.

'; f s HERBERT CORRALL. I

' JAMES HEGGIE. 

